Almost three years ago, James did something no other player of his caliber did before—he walked out on the franchise that brought him into the league to form an unprecedented triumvirate with the Miami Heat.

Superstars have spurned their incumbent teams before. Many times actually. But no one like James, and most certainly not in the same way.

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Game 7 means a whole lot to LeBron's future.

A national audience looked on as the greatest basketball player in the world announced that he would be leaving the Cleveland Cavaliers. And why? To win championships and build a dynasty.

James ceded to the expectations that were set for him while he was still in high school. Preordained a star well before he even reached the professional ranks, James was supposed to be the second coming of Michael Jordan, someone who collected championship rings like it was a hobby.

Seven years into his career, James emerged from the NBA playoffs still empty handed.

It took Jordan seven seasons to win his first ring. When put in that context, James wasn't far behind by any means. When looking at his supporting cast, he was.

He wasn't given a Scottie Pippen. At the time, he had an aging Shaquille O'Neal and an insufficient Antawn Jamison and Mo Williams. They weren't enough, and they were never going to be enough.

So James fled, seeking the comfort of South Beach, where Dwyane Wade and Chris Bosh were waiting. And he was hated for it. Despised to his very core. For his television special, for his decision in general, for his hopeless ego—all of it.

James, meanwhile, sauntered on down to sunny Miami, where he made a pledge that was worthy of appearing in Gilbert's open letter.

The Heat would win eight championships (or more). That was his promise. He had signed on six, but that didn't matter. Reality was a formality.

"Once the games start, it's going to be easy," James said back in 2010.

It hasn't been.

Growing pains followed the Heat through their first season together. Snarky retorts in postgame pressers coupled with his late-game failures (which we now know to be exaggerated) made him a villain. Falling to the Dallas Mavericks in the 2011 NBA Finals only perpetuated this persona.

Few teams are expected to win titles in their first season together. The Heat weren't most teams, though. James left the confines of Cleveland for instant gratification. Anything less than a title was unacceptable.

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James eventually got that title, repairing most—if not all—of his image in the process. A second straight finals appearance culminated in James' first-ever NBA championship. For the first time of his career, he was actually on top.

Fast forward to the here and now, and James is within grasp of his third consecutive finals berth and a second straight title. All that stands between him, the Heat and the opportunity to spur legitimate dynasty chatter is one Game 7 victory over the Indiana Pacers. That's it.

Getting past the Pacers has never been the issue, though. It's what happens if he doesn't.

Should the Heat lose, James won't receive the bulk of the blame. Partly because he's redeemed himself in the public's eyes, but mostly because he's carried Miami.

Bosh and Wade have disappeared in the Eastern Conference finals, leaving James to fend for himself all over again—just like he did in Cleveland.

That's what will be remembered if the Heat fail to come out of the Eastern Conference. James will have deserted the Cavaliers for what? One championship and a dynamic that is all too familiar to the one he loathed in his first home? That's not enough. Not after what he promised.

He didn't leave the Cavs for just one championship. He left to build a dynasty, one that he will fall well short of actualizing if he loses in Game 7.

Remember, time isn't on James' side. The summer of 2014 and all the uncertainty it brings is rapidly approaching. When it arrives, what's he to do? Stay in Miami with an aging Wade? Revert to his roots in Cleveland? Join the Los Angeles Lakers?

This Game 7 isn't for a championship; it's for something more. What happens next season won't matter as much if the Heat can't win now. They've progressed each year. From making the finals to winning a championship to closing out the regular season as the best team in the league, they have taken great strides to improve. Now they've reached a point where there's nowhere to go but down, and that's a dangerous place to be.

Large portions of James' legacy rest upon this Game 7. His future was always going to be determined by how he and the Heat fared in his first four seasons in Miami. A loss against Indiana forces us to consider whether or not the Heat have peaked.

Wade is not going to get better with age. Assembling a prolific supporting cast around the Big Three isn't going to become easier. More championships aren't just going to fall into their lap.

This game is then for James' future, or a good chunk of it. Not just in Miami—in general.

What player has faced this type of game in their prime before? Jordan left the Chicago Bulls on his own terms (numerous times). Kobe Bryant has threatened to leave the Lakers before, but never has. His legacy has never faced the possibility of being shaped by one game. James' is about to.

"It's going to be tough," James said of Game 7 (via Brian Windhorst of ESPN.com). "I probably won't be able to relax until the game starts."

One win. That's all James needs to buy himself more time, to prolong the shelf life of his initial promise and avoid facing a harsh reality he didn't envision accosting this soon.

That's all he needs to maintain control of his destiny, before the very time he is trying to buy forces his hand, potentially leaving him to become a victim of his own promise without the possibility of an actual escape.